Plant growth regulation



Patented May 5, 1953 U N I T ED S TATES FATE NT" F F I C E PLAIN?!GROWTH REGULATION? Nathaniel. Tisohler, Palmyra, N. J assignorto-SharpIcs Chemicals Inc., a corporation of Dela.-

ware

N'mDrawihgm Application October 31, 1951, Serial No. 254,190

on, o a I one -N R1 Hz cures-on in which R1 and R2,. taken individually,represent one of the group consisting of. the. hydrogen atom and. alkyl,alleanol and cycloalkyl radicals, and taken collectively, represent oneof the group consisting of polymethylene and oxapolymethylene radicals,as well. as with compositions which when in the presence. of water yieldanions, of such acids, e. g.., salts of said acids.

The invention is concerned more. particularly with the eXo-cis isomericform of. the above. compounds as active ingredients.

For convenience and. to avoid repetition, all references made herein toactive ingredients of the invention. are to he construed as meaning. theeXo-cis form.

Phytotoxic compositions containing, at. least. one of the aforesaidacids, per se or in chemically equivalent form, are highly efiective forthev purpose, and it is a feature of this invention to providecompositions containing the above active inredients in admixture withsimple, readily available materials which enhance, or intensify theplant response activity of the above active ingredients. These and otherfeatures will become apparent to persons skilled in the art as the.speciiication proceeds.

(Jo-pending. application Serial. No, 81,026, filed March 11, 1949, byNathaniel Tisehler and Ernest P. Bell, issued as U. S- Patent No..2,576,080 on November 20, 1951, teaches the. efilcacy of the3,6-endoxohydrophthalic acids and their derivatives in bringing aboutuseful plant response elsuch as leaf abscission (partial or complete),

blossom thinning, vine-kill, total destruction of the plant, oradventitiousroot formation, the particular plant response manifesteddepending to a large extent upon the applied concentration of theresponse agent, technique of application, and the species and degree of,maturity of the plant undergoing treatment,

The preparation and use of the 3,6-endoxohexahydrophthalamio acidsrepresented by the above formula, per seor; in equivalent form, forplant response purposes, particularly described and claimed in. theco-pending application of NathanieLTischljer andErnest P. Bell, SerialNo. 254,189, filed of even date herewith. That application is acontinuation-in-part of said first-mentioned application.

The above mentiened' compounds as applied to plants may be in the formof the acids per se or in chemically equivalent form, such aswatersoluble salts of the acids. Any such acid and its chemicallyequivalent forms have the common property of yielding the same speciesof anions in the presence of water, and hence are considered to beequivalentfor plant response purposes.

Thus the acids are the active-material's, and this is so whether theyare used as such or in chemically equivalent forms, such aswater-soluble sa-lts. These changes at the carboxyl groups are merechanges in form rather than changes in substance.

Among the water-soluble salts of particular interest there may bementioned sodium, potassium, calcium, strontium, magnesium, aluminum,iron, cobalt, nickel, zinc, cadmium, mercury, copper, and ammoniumsalts, mono-, di-,. and trialkyl-a-mmonium salts; mon-o.-, dti-, andtrialkanolammoniumsalts, mixed alkylalkanolammonium salts whichare'N-substituted in the ammonium radical by from: 2 to. 3 radicals, oithe type indicated, monoand dicycloalkylammonium salts, as wellassaltsol' heterocyclic amines; such asmorpholine, piperidine,pyrrolidine, and hexamethyleneimine.

Turning now' the present. invention, in which 3,6-endoxehexahydrophthaiamic acids (per se or in e uivalei'lt. form); orthe l nd des ri above are the active plant, response. ingredients of mynew. compositions, it is pointed out that said acids are! appreciablysoluble in Water. The other forms: are also water-soluble. Some of themare highly soluble, while others have a lesser degree 0i solubility.However, it is preferred to employ in which the meanings of R1 and R2are the same as in the above formula which represents the acids.

Although the present applicant does not wish to be bound by anyparticular theory as to the mechanism whereby useful plant responseeffects are produced, a considerable amount of experimentation stronglyindicates that said effects are brought about by the existence inaqueous media of anions of the type illustrated above. A salient featureof this theory is that any acid of the invention, when applied per se,or in other form, to a living plant, makes the desired anions availableto the plant.

The desired anions are made available by virture of the fact that theacids per se, and their other forms, are water-soluble and ionizable.Therefore, when such a compound is absorbed into the vascular system ofa plant, it dissolves in the aqueous plant juices and provides thefunctioning anions. The resulting physiological activity is believed tobe ascribable to the presence of such anions. The acids per se and theirequivalent forms may thus be regarded as very convenient media forfurnishing the desired anions to susceptible portions of the plant.

It follows, therefore, that the acids per se and their other forms areequally usable, the foregoing compounds being highly effective for theintended purpose,

I have discovered that the amount of the respective compounds used toproduce a given plant response effect may be markedly reduced, or theplant response effect obtained with a given amount of active ingredientmarkedly increased, by admixing with any said compound or compounds, oneor more of the group consisting of ammonium and substituted ammoniumsalts of the strong mineral acids, e. g. of sulfuric acid, hydrochloricacid, nitric acid and phosphoric acid, e. g. orthophosphoric acid; saidsalts being either in neutral or acid form. Particular substitutedammonium salts are the alkylammonium salts, alkanolammonium salts, andmixed alkylalkanolammonium salts.

Examples of such salts are ammonium sulfate, chloride, nitrate andphosphate; ammonium acid sulfate; ammonium dihydrogen phosphate andammonium monohydrogen phosphate; mono-, di-, and trialkylammoniumsulfates, chlorides,

nitrates and phosphates, having from 1 to 4 car-' bon atoms in eachalkyl radical; mono-, di-, and trialkylammonium acid sulfates andphosphates having from 1 to lcarbon atoms in each alkyl radical; mono-,di-, and trialkanolammonium.

sulfates, chlorides, nitrates and phosphates, having from 2 to 3 carbonatoms in each alkanol radical; mono-, di-, and trialkanolammonium acidsulfates and phosphates, having from 2 to 3 carbon atoms in each alkanolradical; mixed alkylalkanolammonium sulfates, chlorides, nitrates andphosphates, which are N-substituted by from 2 to 3 radicals of the typeand carbon content indicated; and mixed alkylalkanolammonium acidsulfates and phosphates which are N-substituted by from 2 to 3 radicalsof the type and carbon content indicated.

As pointed out above, the sulfates and phosphates contemplated includeboth the acid sulfates and phosphates and the neutral sulfates andphosphates, and mixed neutral sulfates and phosphates, that is sulfatesand phosphates in which the cations are different.

The preparation of the sulfates, chlorides, nitrates and phosphates maybe accomplished by any means known to the art, and suitable methods willbe found in the literature.

Preparation of the 3,6-endoxohexahydropthalamic acids may readily beaccomplished by reacting exo-cis-3,6-endoxohexahydropthalic anhydridewith ammonia or a primary or secondary amine, reaction proceeding inaccordance with the equation:

wherein R1 and R2 have the same meanings as in the formulas given abovefor the acids and the anions derivable therefrom.

Examples of primary and secondary amines which may be reacted with theabove anhydride to yield the corresponding N-substituted 3,6-endoxohexahydropthalamic acid are methlamine, ethylamine, propylamine,butylamine, amylamine, hexylamine, heptylamine, octylamine, nonylamine,decylamine, undecylamine, dodecylamine, dimethylamine, diethylamine,dipropylamine, dibutylamine, diamylamine, dihexylamine,methylethylamine, ethylpropylamine, propylbutylamine, butylamylamine,amylhexylamine, methylundecylamine, cyclopropylamine, cyclobutylamine,cyclopentylamine, cyclohexylamine, dicyclopropylamine,dicyclobutylamine, dicyclopentylamine, dicyclohexylamine,cyclopropylamylamine, cyclopropylhexylamine, cyclobutylmethylamine,cyclobutylbutylamine, cyclopentylmethylamine, cyclopentylheptylamine,cyclohexylmethylamine, cyclohexylethylamine, cyclohexylpropylamine,cyclohexylhexylamine, monoethanolamine, monopropranolamine,diethanolamine, dipropanolamine, ethanolpropanolamine,methylethanolamine, propylpropanolamine, nonylpropanolamine,amylethanolamine, decylethanolamine, ethylethanolamine,cyclohexylethanolamine, cyclohexylpropanolamine, pyrrolidine,piperidine, hexamethyleneimine, and morpholine.

Theoretically, if a free acid is desired the anhydride and ammonia oramine as shown in the foregoing equation are brought together,conveniently in equimolar proportions, and mixed, such as by stirring,until reaction has taken place. The reaction may be conducted in aqueousor no-aqueous media, the latter being frequently preferred. Suitablenon-aqueous media are those which are substantially inert toward thereactants and products, such as hexane, kerosene, benzene, toluene,xylene, etc.- However, if

. cyclohexyl-lll-methyl-, N-cyclohexylsN-propyh, N-cyclohexyl-N-hexy1, N-ethanol, N propanol, Nit-diethanol, BEN-ditpropanolN-ethanel-N-propanol, N-methyl-llltendency of some of the products: todecompose under such conditions.

A useful -modificationoi the above procedure consists in employing twomoles or more of arm monia or amine per mole of the anhydride, a saltbeing ordinarily obtained, particularly if the free acid. as formedremains in solution. One mole of ammonia or amineserves to react withthe anhydrid'e to form the corresponding amide-acid as shown in theabove equation, and a second mole of ammonia or amine serves toneutralize the acid so formed.

Salts may be obtained by preparing the appro priate free acidasdescribed above, followed by neutralizing the acid with thesame or adiilerent amine. n the other hand, the free acid may be neutralizedwithan inorganic base. In many instances it is veryconvenient to omitisolation of the acid, can'yi ng out the neutralization in the reactionmixture in which the acid was prepared. In other instances it maybe"desired to isolate the acid, and neutralize it in a separate step.Preferred alkyl radicals for attachment to the amide nitrogen atonr'ofthe acids are those having from 1 to 12 carbon atoms, such asmethyl,

ethyl, propyl, butyl, amyl, hexyl, heptyl, octyl, 'nonyl, decyl,undecyl, and dodecyl.

Preferred alkanol radicals for attachment to said amide nitrogen atomare those having from 2 to 3 carbon atoms, such as ethanol and propanol.P're ferred cycloalkylradicals for attachment to said amide nitrogenatom are those having from 3 to 6 carbon atoms, such as cycl'o-propyl,cyclobutyl, cyclopentyl, and cyclo-hexyl. Exampl'es'of polymethylene andoxapolymethylene radicals suitable for attachrrent to said amidenitrogen atom are tetram'ethylene, pentamethylene; hexamethylene, and3-oxapentamethylene radicals. The totality of carbon atoms insuchradical or radicals asm'ay be attached to the amide nitrogen atom ispreferably not" more than: 12.

Examples of acids of the iiwerltion are the parent acid, namely, 3,6endonohexahydrophthalamic acid, and N-substitutedacids as follows:N-methyl-, N-ethyl-, N-propyl-, N-butyl-, N-amyl--, N -hexyl N-heptyl-,N-oetyl'-, N-

' nonyl N-decvh, N-undecyl-, 'l l-dodecyh, NIN- N,N-dicyclopropyl-, N,N-dicyclobutyl-,v N ,N-diethanol, N-ethyl N-ethanol,N-propyl-N-propanol, N-nonyl-N-propanol, N-amyl-N-ethanol, N-decyl-N-ethanol', N-cyclohexyl-N-ethanol, N- cyclohexyl-N-propanol,N-tetramethylene-, N- pentamethylene-, N.-hexamethylene-, and N-3-oxapentamethylene-3,6-endoxohexahydrophthalamic acids.

The amount of additive or intensifier to be admixed with the activeingredient-may vary over a very wide range. A. small amount will producea useful intensifying effect, and since some of the intensifiersemployed in this invention are also good. fertilizers, especially in thecase of ammonium sulfate, ammonium nitrate, and diammonium hydrogenphosphate, I contemplate the use of proportions of intensifier far inexcess of those proportions producing optimum intensifying action.

For practicable purposes, proportions oi. intensifier to activeingredient of from 1:10 to 20:1, and particularly from 1 :2 to 5:1 are.very useful when the primary purpose of the application of the admixtureis the enhancement of phytotoxic effect. On the other hand, whensubstantial fertilization of soil is also desired, the proportion ofintensifier to active ingredient may run quite high, such as up to :1,or even more.

The intensifier and the active ingredient may be admixed in any desiredmanner such as by mere mechanical mixing in solid form, or while insolution in a common solvent such as water.

In the latter case the solution may be marketed as such, or if desired,may be dried at temperatures sufiicientl'y low to prevent decompositionof the active ingredient, such as up to say 100 C. In any case, it ispreferred to have a solid admixture in finely divided form andsufficiently dry to be free flowing. 1

The admixtures are applied to the crop or plants in. any desired manner,such as in the form of" a solid, for example, by dusting, or in theform-of a liquid, for example, by-spraying.

Compositions may be formulated by mixingthe admixture containing theintensifier and active ingredient with any desired liquid or solidcarriers, such as any of the finely divided solid carriers knownin thedusting art, which are preferably of largesurface area, such as clay,for example, fullers earth, pyrophyllite, talc, bentonite, kieselguhr,diatomaceous earth, etc. Any" o: the commercial clays available on the:narlretin finely divided form may be used, and particularly those whichare normally employed as insecticide carriers. Commercial clays, it willbe understood, are generally identified by trade names (reflecting thesource and mode of processing), of which Homer Clay, Celite, and Tripolimay be mentioned as typical.

Non-clay" carriers which may be formulated with my admixture include,for example, sulfur, volcanic ash, calcium carbonate, lime, by-productlignin, li-gnocell ulose, flour, such as Wood, walnut she'll, wheat,soybean, potato, cottonseed. etc.

Any desired mixture maybe prepared by any suitable method. Thus, if asolid, the active ingredient may be ground to a fine powder and tumbledtogetherwith the intensifier, or the intensifier and the activeingredient may be ground together; alternatively, active ingredient inliquid form, including solutions, dispersions, emulsions, andsuspensions thereof, may be admixed. with the intensifier-in finelydivided form in amounts small enough. to preserve the free-flowingproperty of the final dust composition. or excess liquid may be removed,such of the admixture with the carrier. commonly done at the time ofspraying. Prefthat the composition be in finely divided form.

Preferably, the dust containing the active in 'gredient should besuificiently fine that substantially all will pass through a 50 meshsieve,

and more particularly through a 200 mesh sieve. Excellent results havebeen obtained in which the dust composition is comprised predominantlyof particles in therange from to microns.

"Finer dusts, such as those consisting largely of particles in therange-of 5 microns and below have excellent covering capacity but aresomewhat more subject to drift and are more ex pensive to prepare.

For spray application the admixture may be dissolved or dispersed in aliquid carrier such as water or other suitable liquid.

Aqueous solutions or dispersions are economical and desirable. Ingeneral, the choice of the particular liquid carrier employed will beguided somewhat by prevailing circumstances, such as its availability,its solubility or dispersion characteristics toward the particularadmixture employed, and/or its toxicity toward the plants undergoingtreatment. In general, water is an excellent liquid carrier.

Thus, spray formulations comprising the active ingredient in the form ofa solution, suspension,

dispersion, or. emulsion, in aqueous or nonaqueous media may beemployed.

- Emulsions or dispersions of theadmixture in the liquid carrier may beprepared by agitation This is erably however, the agitation should takeplace in the presence of an emulsifying or dispersing agent(surface-active agent), in order to facilitate the preparation of saidemulsion or dispersion. Emulsifying and dispersing agents are well knownin the art, and include, for example, fatty alcohol sulfates, such assodium lauryl sulfate, aliphatic or aromatic sulfonates, such assulfonated castor oil or the various alkaryl sulfonates (such as thesodium salt of monosulfonated nonyl naphthalene or tertiary dodecylbenzene), and non-ionic types of emulsifying and dispersing agents suchas the high molecular weight alkyl polyglycolethers or analogousthioethers such asthe decyl, dodecyl and .tetradecyl polyglycolethersand thioethers conmaltose, lactose, raflinose, trehalose, dextrins suchas White dextrin, canary dextrin, British gum, etc., honey, molasses,maple syrup, maple sugar, and starch syrups such as corn syrup,

etc.

For adjuvant purposes, any desired quantity of w-etting'agent may beemployed-, 'such -asup to 250% or more based on active ingredient. Forwetting purposes, the amount of adjuvant used may be considered to bethat required to impart the desired wetting qualities to the spraysolution as formulated, such as approximately 0.05% by weight of thespray solution. The useof considerably larger amounts is not based uponwetting properties, although present, but is a function of thephysiological behavior of the wetting agent after spraying upon theplant. It should-be considered. that once the solution has been sprayedupon the plant, the concentration of wetting agent existing upontheplant is in no sense a function of the concentration existing in theoriginal spray solution. Thus, evaporation might concentrate the wettingagent considerably, or the presence of dew on the plant surfaces, or ofplant juices on the plant surfaces might considerably dilute this agent.

It-will, of course, be understood that wetting agents, particularly whenin solid form, may be compounded with the admixture when in solid form.

Although the admixture of active ingredient and intensifier may beapplied to the growing plant in concentrated form, it is usuallydesirable to employ liquid or solid formulations, for example, asdiscussed above, in which the active ingredient constitutes lessthan 30%by weight of the total, such as less than 10% and even as low as 0.1%.When it is intended that the intensifier shall also have a substantialeffect as a fertilizer, it may, of course, be present in verysubstantial quantity with or without the presence of a solid or liquidcarrier.

Other substances than the carrier and/or surface active agent may beincluded in'solid or liquid formulations if desired. Thus, activeingredients other than those disclosed herein and compatible with theadmixture may be added if desired for any particular purpose.

-Also substances may be added to bring about various physicalimprovements such as the prevention of lumping during storage, orimprove- -ment with respect to coverage, moisture adsorpclude singly orin combination, substances such as fungicides, insecticides,bactericides, or types of plant response agents other than those agentsdiscussed herein.

In practice of the process as applied to defoliation, the rate ofapplication (i. e. the amount of admixture per crop unit)- for bestresults will depend among other factors upon the species of plants beingtreated and upon their maturity. In any event, the amount of activeingredient employed for the same plant response effect will besubstantially lower than when the intensifier is not present.

As a rule the more mature the plant at the time of application, the lessactive material is required. In practice, the crop is normally treatedfor defoliation purposes, 1 or 2 weeks prior to harvesting. In someinstances, more than one application may be desirable, especially ifheavy rains or winds should occur soon after the application, or toobtain an accumulative efiect. Then too, in order to avoid possibleinjury to any particular crop, it may be desirable for an inexperiencedoperator to apply the defoliant initially at a relatively low rate, andto follow 9. with a second application if necessary afterqob servationof the first effects, to obtain the de gree of defoliation desired.

Use of dosages greatly in'excess of the minimum required for gooddefoliation may result in shock to the plant with attendant injury tothe remainder of the plant.

In fact, the plant response agent of the prescut invention are effectiveherbicides when used c in amounts substantially greater than thoserequired for defoliation, and they may be used advantageously for thekilling of plants or vines (as in the case of potatoes) when desired,such as, for the killing of undesired plants, for exam ple, weeds orgrasses, or for the killing of crops, irrespective of whether suchundesired plants or intensifier is also a fertilizer.

crops are of species which lend themselves to defoliation.

Thus when defoliation is the objective the quantity applied should besufficient to cause at least the major portion of the leaves to dry upand/or to drop from the living plant, but insufficient to causesubstantial herbicidal action on the plant. On the other hand, whenplant killing i the objective, any amount suflicient for this purposemay be applied. In the latter connection, since different species ofplants vary markedly in their relative resistance to herbicidal action,selective killing of plant species may be practiced. Such selectivitymay be varied by compounding, such as with adjuvants, for ex ampie,wettng agents, in addition to the use of an intensifier.

I am aware of the fact that it has been proposed to use certain ammoniumsalts suchas ammonium sulfate, in combination with phenolic substances,such as dinitroalkylphenols and pentachlo'r'ophenol, for plant responsepurposes. The purpose of such use of ammon um salts as explained byCrafts and Reiber, Hilg'ardia, volume 16, pages 48'7-499, and by Crafts,Science, volume 108, pages 85-86, is to make ava lable the free phenolat the plant surface from an aqueous solution of a water-soluble salt ofsaid phenol.- The phenol in such cases isthe active plant responsesubstance and is continuously regenerated at the plant surface from itswater-soluble salt by virtue of the presence of the ammonium salt. Asthe free phenol is absorbed by the plant surface, further free phenol isgenerated under equilibrium conditions. The plant response effect of thefree phenol is not enhanced or intens fied by suchprocedure, or in otherwords, is substantially the same as that obtained by the applicationdirectly to the plant of a similar ouantity of free phenol. In view of.the insolubility of the phenol in water; this procedure is ado ted inorder to make ava lable the use of water as a vehicle for applying theplant response agent, i. e. herbiside, to the plant surfaces.

In the case of my invention. on the other hand, the plant responseeffect obtained from a given quantity of active in redient is greaterthan that obtained by the application of the same quantity of theparticular a tive ingredent to the plant in the absence of myintensifier. In act, the plant response effect obtained with the samequantitv of active in redient may be increased many times by theaddition of larger quantities of my intensifier. The intensification beins to manifest itself by the addition of a small proportion of myintensifier and increases to a point of optimum intensification by theaddition of increasing proportions of intensifier. For optimum plantresponse effects, the proportion of intensi- The exact mechanism bywhich the intensification of the active ingredient is obtained in thepractice of my invention is not known. However, such intensification iscogently demonstrated by the following examples which are by way ofi1lus-- tration and not of limitation, it being understood that anyother intensifier of the invention may be subst'tuted for the ammoniumsulfate employed therein.

, In each example below, a group of plants was not treated and was keptas a control, the untreated group being similar to the treated group orgroups. All plants (both treated and un treated) used for a test were ofthe same age and had been grown at the same time and under the sameconditions. After the test was commenced, treated plants and untreatedcontrols were again kept under the same conditions and therefore weresubjected to comparable growing conditions. In all instances, theuntreated controls grew normally.

EXAMPLE 1 Aqueous solutions of sodium N,N-diethyl-3,6-endoxohexahydrophthalamate of the following respective concentrationswere spray-misted by meansv of a small DeVilbiss atomizer ontoindividual groups of thirty-two potted Dwarf Horticultural bean plants:0.031%, 0.062%, 0.125%, and 0.25%. The plants were at a stage of growthat which the first trifoliate leaf was still furled.

Each group of thirty-two plants was arranged uniformly in a 2 foot by 3foot area, and 3 ml. of test solution was uniformly sprayed in thedescribed manner onto the area. This rate of application corresponds toapproximately 6 gallons per acre: this low volume rate simulatespractical conditions of aeroplane spraying. Thus the amount of activeingredient was 0.125, 0.25, 0.5, 1.0, and 2.0 ounces, respectively, peracre.

A. parallel series of tests was carried out in which the aqueoussolutions of the above concentrations of the active ingredient alsocontained ammonium sulfate as an intensifier, the weight ratio ofintensifier to active ingredient being 5:1

in all cases. Thus the amount of ammonium sulfate was 0.625, 1.25, 2.5,5.0, and 10.0 ounces, respectively, per acre.

Observations made three days after the plants were treated are given inTable 1.

several symbols are employed in this table, their meanings being asfollows in this example and wherever applicable in the other examples:ltzlight or lightly mod:moderate or moderately sevzsevere or severely bnburned retzretarded adh adhering czuntreated control PLEprimar'y leavesTsitiifoliafi shoots 11 68, for example, means each of six plants had asingle primary leaf abscised; 2B, for example, means each of two plantshad both primary leaves abscised.

Table 1 12 were prepared: 0.0006%, 0.005%, and 0.0075%.

Other aqueous solutions were prepared having the same concentrations ofthe same active in- Physiological efiects Cone. of active ingredient,

Ounces per acre WlthOllt (NHOzSO;

with (NH4):SO4

sev bn Control tests using the intensifier in the absence of activeingredient were conducted. Groups of plants wholly analogous to theabove groups were treated with ammonium sulfate solutions of variousconcentrations, using the abovedescribed method of application. Even ata dosage of 5 pounds of ammonium sulfate per acre, the plants were notaffected. Similar control tests were carried out in the other examplesand in no case were the plants affected by the intensifier.

Thus it is seen that the above active ingredient is highly phytotoxicper se, even when employed in quite low dosage, and that its phytotoxicproperties are markedly enhanced, or intensified, by admixing the activeingredient with an intensifier of this invention.

EXAMPLE 2 Compounds employed in this test were as follows, the capitalletters identifying the compounds in Table 2 below:

gredients as indicated in the preceding paragraph; in addition, eachsolution contained 0.05% of ammonium sulfate. Thus the weight ratio ofintensifier to active ingredient ranged from 6.7:1 to 83.3:1.

These solutions were applied to potted young Dwarf Horticultural beanplants at a growth stage at which some of the first trifoliate leaveswere still furled and others were unfurling. Separate groups of eightsuch plants were dipped to the first nodes into the respective testsolutions, and the excess solution was shaken off. Approximately 2 ml.of solution remained on each plant. Thus the dosage per plant of activeingredient, depending on the concentrations of the test solutions, wasapproximately 12, 25, 50, 100, and 150 micrograms, respectively. Thedosage per plant of intensifier was constant, amounting to approximately1000 micrograms.

Observations were made three days after treatment and are summarized inTable 2.

Table 2 PHYSIOLOGICAL EFFECTS Active ingredient per plant Compound 12micrograms 25 micrograms micrograms 100 micrograms 150 micrograms Aalone4S; adh PL-some It 213. 38' adh 5B. 38; adh 5B, adh PL- 4B,2s- (111 bn,some as C. PLmod bn. PLmod bn. fro en. froze n PL AWith(NH|)2 0|.1B;adhPL-ltbn.-. 7B. 18; adh 4B, 28; adh 4B. 28; adh 8B.4F;adh PL-PIrsev bn. PLsev bn, PLshrivelled shrivelled and pfirly shrivand frozen.frozen. e e 13 1 2S;adh PL-lt bn.-- PLltbn 3B, 28; adh 8B 7B; adh PL-PLmod bn. shrivelled and BVVith(NH4)2 Ol 1B; adh PLmod 63. 2S; adh 7B;adh PL 5B, 18; adh 5B dh PL bn. PLshrivelled shrivelled and PLshrivelledshrivelled and and frozen. frozen. frozen. frozen. Calorie AS ASKSffladh PL- 313, IS; adh 5B; adh PL 11. PLmodb th (NH,),S0 PLlt bn 6B;adh PL- 6B. 18; adh 6B. 28; ad h 4B s dhPL mod bn. PLLsevbn.PL-shrivelled shrivelled and and frozen. frozen.

The term frozen as used to describe a condition of the leaves of a planttreated with a defoliant denotes that condia wok and drastic responsethat no abscission layer has formed. The leaves then cling tenaciouslyto the plant although t e leaf blade and petiole are dead andshrivelled, and show no tendency to abscise. Thus, 1t 15 to beunderstood that freezing or shrivelling of leaves indicates a morephytotoxic condition tion in which the leaves have undergone such whenthe leaves actually abscise.

Aqueous solutions having the following concentrations of theserespective active ingredients test:

EXAMPLE 3 The following compounds were employed in this A.Diethylammonium N,N-diethyl-3,6-endoxohexahydrophthalamate. B.Dibutylammonium N ,N-dibutyl-3,6-endoxohexahydrophthalamate.

13 c. N butyl 3,6 endoxohexahydrophthalamic acid. D. N,N diisopropyl 3,6endoxohexahydro phthalamic acid.

The capital letters are used to designate these compounds in Table 3below.

Aqueous solutions having the following respective concentrations ofthese respective active ingredients were spray-misted bymeans of a smallDeVilbiss atomizer onto individual groups of eight potted DwarfHorticultural bean plants (with the first trifoliate leaf still furled)0.016 0.031%, 0.062%, 0.125%, 0.25%, and 0.5%. Each test solutioncontained ammonium sulfate in a :1'weight ratio of intensifier to activeingredient.

Each group of plants was arranged uniformly in a 2 foot by 3 foot area,and 3 ml. of test solution was sprayed thereon as described above; thisrate of application corresponds to approximately 6 gallons per acre.Thus the amount of active ingredient per acre was 0.125, 0.25, 0.5, 1.0,2.0, and 4.0 ounces, respectively; the amount of ammonium sulfate wasfive times as much as that of the active ingredient, in each instance.

Table 3 summarizes observations ,made four days after treatment.

also acid salts in cases where such exist) of the strong mineral acidsmentioned herein, such as monoalkylammonium, dialkylammonium, ortrialkylammonium salts, preferably have from 1 to 4 carbon atoms in eachalkyl radical. The alkanolammonium salts such as monoalkanoh ammonium,dialkanolammonium, or trialkanoh ammonium preferably have from 2 to 3carbon atoms in each alkanol radical. The mixed alkyl-i alkanolammoniumsalts such as monoalkyl mono= alkanolammonium, dialkyl monoalkanolammmnium, or monoalkyl dialkanolammonium'pref erably have from 1 to 4:carbon atoms in each alkyl radical and from 2 to 3 carbon atoms in eachallranol radical.

The following examples apply to both'the active ingredient and theintensifier.

Examples of monoa'lkylam'monium salts are the monomethylammonium,monoethylammonium, monopropylammonium, monobutylammo nium,monoamylammonium, mono'hex-ylammo-' nium, monoheptylarnmonium,monooctylam'mm nium, monononylammonium, monodecylammonium,monoundecylammonium, monododecylam-i monium and similarmonoalkylammonium salts of such acids.

Examples of dialkylammonium salts are the dimethylammonium,diethylammonium, dipro Table 3 PHYSIOLOGICAL EFFECTS Active ingredientper acre Compound 0 125 ounce 0.25 ounce 0.5 ounce 1.0 ounce 2.0 ounces4.0 ounces A As C 1S; adh PLlt 5B, 38; adh 5B, 38; adh 6B, 2S; adh 6B,IS; adh bn; TS-as C. PL-mod PL-frczeu; PL-frozen; PLfrozen; b n; T'S T SIn 0 d TS-sev ret. TS-sev ret.

mod ret. ret.

B do 1. 2S;.adh PL-morl 7B, 28; adh. 5B. 18; adh 5B, is; adh 3B, 28;.adh

c; do 1B, ssyadh PIS- 7B. 28; adh 5B; adh PL- 5B, 3s; adh 2B, 2s; adhmod 'bn", TS- PL-,frozen; irozen;TS- PLfrozen; PL-frozen; 1t ret. TtS n10 d m'od re't. TSsev ret. TS-sev ret.

D 1B; adh PL- 63; min PL- 5B, 28; adh, 6B, 18; a'dh 5B, 28; adh 6B; adhPL- lt bn; TS- some bn, some PLfrozcn; PL-frozen: PL-frozen; frozen;'lS- as C. shrivelled; 118- T S 'm o d 'I S m o d TS-sev ret. sev ret.

modret. retrct.

Phytotoxic efiects are less pronounced when no intensifier is used.

When the active ingredients are used in the form of the acids per se,aqueous solutions containing such acids probably contain non-ionizedacid in equilibrium with ionized material.

The alkylam-monium salts of 3',6-endoxohexahydrophthalamic acids, suchas monoalkylammonium, dialkylammonium, or trialkylammonium saltspreferably have from 1 to 12 carbon atoms in each alkyl radical, thetotality of carbon atoms preferably being not more than 12. Thealkanolammonium sa-lts such as monoalkanolammonium, dialkanolammonium,or trialkanolammonium preferably have from 2 to 3 carbon atomsineachalkanolradical. The mixed alkylalkanolammonium: salts suchasmon'oa'lkyl mono. all:anolammonium,v dialkyl monoalkanolammo ormonoalkyl. dialkanolammonium pref,- erably have'from 1 to 4 carbonratomsin. each alkyl radical and from 2- to 3 carbon atoms in each alkanol'radical. The. cycloalkylammonium salts such as monocycloalkylammoniumand dicycloalkylammonium preferably havefrom 3to 6 carbon atoms in each;cycloalkyl radical, the totality of. carbon atoms preferably being notmore than 12.

pylammonium, dibutylammonium. diamylammonium, dihexylammonium,methylethylammonium,v ethylpropyiammonium, propylbuty1ammonium,butylamylammonium, amylhexylammonium, methylundecylammonium, and similardialkylammonium salts of such acids.

Examples of trialkylammonium salts are, the trimethylammonium,triethylammonium, tripropylammonium, tributylammonium,methyldiethylammonium, ethyldipropylammonium, propyldibutyl'ammonium,methyldiamylammonium, ethyldiamylammonium, methylethylpropylammonium,ethylpropylloutylammonium,- and similar salts of such acids.

Examples of monoalkanolammonium salts are the monoethanolammcnium,monopropanolammonium, and similar salts of such acids:

Examples ofv dialkanolammonium' salts are the diethanolammonium,dipropylammonium, ethanolammonium, dipropanolammonium,ethanolpropanolammonium and similar salts of such acids.

Examples of trialkanolammonium salts are the triethanolammonium,tripropanolammonium, ethanoldipropanolammbnium, propanoldiethan'ol- The.alkylammonium. salts: (neutral salts, and ammonium and similar salts of.such acids.

' Examples of monoalxyl monoalkanolammonium salts are themethylethanolammonium, ethylethanolammonium, propylethanolammonium,butylethanolammonium, methylpropanolammonium, ethylpropanolammonium,propylpropanolammonium, butylpropanolammonium, and similar salts of suchacids.

Examples of dialkyl monoalkanolammonium salts are thedimethylethanolammonium, diethylethanolammonium,dipropylethanolammonium, dibutylethanolammonium,dimethylpropanolammonium, diethylpropanolammonium,dipropylpropanolammonium, dibutylpropanolammonium,methylethylethanolammonium, methylethylpropanolammonium,ethylpropylethanolammonium, ethylpropylpropanolammonium,propylbutylethanolammonium, propylbutylpropanolammonium, and similarsalts of such acids.

Examples of monoalkyl dialkanolammonium salts are themethyldiethanolammonium, ethyldiethanolammonium,propyldiethanolammonium, butyldiethanolammonium,methyldipropanolammonium, ethyldipropanolammonium,propyldipropanolammonium, butyldipropanolammonium,methylethanolpropanolammonium, ethylethanolpropanolammonium,propylethanolpropanolammonium, butylethanolpropanolammonium, and similarsalts of such acids.

The following examples apply more particularly to the activeingredients.

Examples of monocycloalkylammonium salts are the cyclopropylammonium,cyclobutylammonium, cyclopentylammonium, cyclohexylammonium, and similarmonocycloalkylammonium salts of such acids.

Examples of dicycloalkylammonium salts are 7 the dicyclopropylammonium,dicyclobutylammonium, dicyclopentylammonium, dicyclohexylammonium,cyclopropylcyclohexylammonium, and similar dicycloalkylammonium salts ofsuch acids.

Other substituted ammonium salts contemplated by the invention are thosein which the ammonium radical is substituted by different radicals ofthe kind described above, such as the cyclohexyl-methylammonium,cyclohexylethylammonium, cyclohexyl hexylammonium, cyclopropylmethylammonium, cyclopentyl-butylammonium, methyl cyclohexylethanolammonium, cyclohexyl-propanolammonium, andcyclohexyl-diethanolammonium salts of such acids.

As pointed out above the intensifiers contemplated include both the acidsalts and the neutral salts, and mixed neutral salts, that is salts inwhich the cations are different.

The term plant as used herein is understood to include all portions ofthe plant, such as the roots, stems, leaves, blossoms, seeds, andfruits.

Among the plants which defoliate naturally and which may be defoliatedby the use of this invention, are for example, cotton, potatoes,tomatoes, and beans such as soybeans and lima beans.

Among the noxious weeds against which my compositions may be used asherbicides are the following: bindweed, chickweed, cocklebur, marestail, shepherds-purse, broad-leaved plantain, wild lettuce, ragweed,spurge, dock, and wild carrot.

As pointed out above, certain of the intensifiers referred to herein arewell-known soil fertilizers, such as ammonium sulfate, ammonium nitrate,and diammonium hydrogen phosphate. It follows that the activeingredients in amounts sufficient to cause the desired plant responseaction may be compounded with such fertilizer and ap- 16 pliedsimultaneously therewith. This is particularly applicable topre-emergence or Dre-planting practices for the control of weeds, topost emergence treatment for fertilizing purposes and control of weedsas to such useful crops to which the active ingredients evidence onlyslight or no herbicidal action, such for example as onions, sugar beets,flax, carrots, and cole crops, and otherwise following agriculturalpractices. The proportion of intensifier to active ingredient in suchcases may be as desired, dependent largely upon the amount of fertilizerto be applied per acre, so as to obtain the desired coverage of activeingredient in admixture with the fertilizer. For example, the proportionof intensifier to active ingredient may range from 1000:1 or 500:1 to :1or 200:1.

From the foregoing it can be seen that the endoxo compounds used in thepractice of this invention, whether used as the acids or in some otherform, are highly effective in regulating the growth characteristics ofviable or living plants, and particularly of plants having vascularsystems, when used in admixture with my intensifier. For example, theadmixture may be employed to hasten defoliation of plants whichdefoliate naturally, or may be employed to terminate the life cycle ofplants, or may be employed to retard the growing of seeds, or may beemployed to selectively stunt or terminate the growth of certainunwanted plants to facilitate and favor the growth of wanted plants, ormay be employed to terminate the growth of vines infavor of, or tofacilitate harvesting of, the fruits of such vines, etc. Otherapplications of the invention in the regulation of the growthcharacteristics of plants will occur to persons skilled in the art uponbecoming familiar herewith.

Accordingly, it is to be understood that the particular description isby way of illustration and that the patent is intended to cover bysuitable expression in the claims whatever features of novelty reside inthe invention.

This application is a continuation-in-part of my copending applicationSerial No. 161,255, filed May 10, 1950 and issued as U. S. Patent No.2,576,083 on November 20, 1951.

I claim:

1. A plant response composition comprising a salt of a strong mineralacid with at least one of the group consisting of ammonia, alkyl amines,alkanol amines, and mixed alkylalkanol amines, and at least onewater-soluble compound the anion portion of which is of exo-cisconfiguration and conforms to the structure 17 tion comprising a majorproportion of a soil fertilizing ammonium salt of a strong mineral acid,and a minor but sufiicient proportion for plant response effect of atleast one water-soluble salt the anion portion of which is of exo-cisconfiguration and conforms to the structure CH O in which R1 and R2taken individually represent one of the group consisting of the hydrogenatom and alkyl, alkanol, and cycloalkyl radicals, and taken collectivelyrepresent one of the group consisting of polymethylene andoxapolymethylene radicals.

6. A plant response composition comprising a salt of a strong mineralacid with at least one of the group consisting of ammonia, alkyl amines,alkanol amines and mixed alkylalkanol amines, and at least one compoundwhich when in the presence of water yields anions of exo-cisconfiguration and conforming to the structure OH R /\CH(HJN/ in which R1and R2 taken individually represent one of the group consisting of thehydrogen inwhich R1 and R2 taken individually represent TH-C-N one ofthe group consisting of the hydrogen atom and alkyl, alkanol, andcycloalkyl radicals, and

taken collectively represent one of the group con-- sisting ofpolymethylene and oxapolymethylene radicals.

8. A method for inducing plant response in a living plant, comprisingapplying to said plant a composition comprising a salt of a strongmineral acid with at least one of the group consisting of ammonia, alkylamines, alkanol amines and 18 mixed alkylalkanol amines, and at leastone water-soluble compound the anion portion of which is of exo-cisconfiguration and conforms to the structure in which R1 and R2 takenindividually represent one of the group consisting of the hydrogen atomand alkyl, alkanol, and cycloalkyl radicals, and taken collectivelyrepresent one of the group consisting of polymethylene andoxapolymethylene radicals.

9. The method of claim 8 in which said salt is an ammonium sulfate.

10. The method of claim 9 in which said salt is ammonium sulfate.

11. A method for regulating the growth characteristics of a plant,comprising applying to said plant a plant response compositioncomprising a salt of a, strong mineral acid with at least one of thegroup consisting of ammonia, alkyl amines, alkanol amines and mixedalkylalkanol amines, and at least one compound which when in thepresence of water yields anions of exo-cis configuration and conformingto the structure in which R1 and R2 taken individually represent one ofthe group consisting of the hydrogen atom and alkyl, alkanol, andcycloalkyl radicals, and taken colectively represent one of the groupconsisting of polymethylene and oxapolymethylene radicals.

12. A plant response composition comprising ammonium sulfate and exo-cisdiethylammonium N,N-diethyl-3,6-endoxohexahydrophthalamate.

13. A plant response composition comprising ammonium sulfate and exo-cisdibutylammonium, N,N dibutyl 3,6 endoxohexahydrophthalamate.

14. A plant response composition comprising ammonium sulfate and exo-cissodium, N,N-diethyl-3,6-endoxohexahydrophthalamate.

15. A plant response composition comprising ammonium sulfate and exo-cisN-butyl-3,6-endoxohexahydrophthalamic acid.

16. A plant response composition comprising ammonium sulfate and exo-cisN,N-diisopropyl- 3,6-endoxohexahydrophthalamic acid.

NATHANIEL TISCHLER.

No references cited.

1. A PLANT RESPONSE COMPOSITION COMPRISING A SALT OF A STRONG MINERALACID WITH AT LEAST ONE OF THE GROUP CONSISTING OF AMMONIA, ALKYL AMINES,ALKANOL AMINES, AND MIXED ALKYLALKANOL AMINES, AND AT LEAST ONEWATER-SOLUBLE COMPOUND THE ANION PORTION OF WHICH IS OF EXO-CISCONFIGURATION AND CONFORMS TO THE STRUCTURE